1. Field
Example embodiments of the present invention relate to pixel circuits of organic light emitting display devices, and organic light emitting display devices including the pixel circuits.
2. Description of the Related Art
An organic light emitting display device includes a scan driving unit that provides a scan signal, a data driving unit that provides a data signal, and a plurality of pixel circuits that are driven based on the scan signal and the data signal.
The scan driving unit may sequentially provide the scan signal by selecting the plurality of pixel circuits on a line basis using a shift register. The data driving unit may provide the data signal to the plurality of pixel circuits that are selected on a line basis. Each pixel circuit may provide a predetermined driving current corresponding to the data signal to an organic light emitting diode to display an image corresponding to the data signal.
In general, the scan driving unit may perform a unidirectional scan that sequentially applies the scan signal from the topmost scan line to the bottommost scan line on a line basis, however, a bidirectional scan technique that selectively performs a first unidirectional scan from top to bottom or a second unidirectional scan from bottom to top may also be used.
To perform the bidirectional scan, the scan driving unit may include a shift register for sequentially providing the scan signal from the bottommost scan line to the topmost scan line as well as a shift register for sequentially providing the scan signal from the topmost scan line to the bottommost scan line. Accordingly, because at least two shift registers are used to perform the bidirectional scan, the size of the scan driving unit may be increased, and a bezel of the organic light emitting display device may be increased.